The present invention relates to an electric power source to supply the electric power to an equipment which is transferred to a power saving mode when it is not operated for a predetermined period of time, a power saving control device to transfer the equipment to the power saving mode when it is not operated for a predetermined period of time, or to an image forming apparatus which is transferred to the power saving mode when it is not operated for a predetermined period of time in a standby mode in which an image can be formed instantly, and specifically to a device by which the electric power saving is more promoted.
Recently, in electrical apparatus, for example, apparatus such as an image forming apparatus, various improvements are made according to requirements for power saving. In the image forming apparatus, the apparatus has, for example, a power saving mode by which power consumption is more saved rather than a standby mode by which an image can be instantly formed, and when the apparatus is not operated for a predetermined period of time, the apparatus is automatically transferred into a power saving mode for saving the power consumption, and thus the electric power saving is promoted. On the other hand, for power factor improvement of overall apparatus, and for higher harmonic suppression, recently, a power source, in which a power factor improvement section such as an active filter is provided, is developed.
In this power factor improvement section, the power factor is improved by a switching operation using a switching circuit, and generation of higher harmonic is suppressed.
However, when the image forming apparatus is transferred into the power saving mode, in spite of small power consumption of the image forming apparatus itself, electric power is wastefully consumed by a switching operation of the power factor improvement section, and on the contrary, the electric power saving is prevented.
On the other hand, in order to return the image forming apparatus to the standby mode after the apparatus has been transferred to the power saving mode, it is required to operate an operation section of the image forming apparatus. However, in the operation section of the recent image forming apparatus, a touch-panel is provided to operate such operation visually. However, it is required for the touch-panel to detect the information of a pressed position, and the power consumption for this operation can not be neglected.
Further, recently, as a standard for power saving, the Energy-star is spread, in which, basically, 3 modes are regulated as the power saving mode according to passage of time. However, in the conventional image forming apparatus, 2 switches for the main power supply and the power saving are provided in the operation section, and the apparatus is transferred into the power saving mode by pressing the power saving switch, however, 3 power saving modes according to the Energy-star can not be directly selected.